I am new to rx 8 ownership and my 2004 192 model has today failed its mot test on sky high emissions as I'm new to rotary engines I don't know if there are any specific reasons why they are so high or do I have to start with expensive diagnostics any help would be greatly appreciated

 

You need diagnostics. Since you said mot, I take it you're in the UK. Are there shops or parts stores that offer free code reading, like Autozone and other places in the US? If not, you can buy a code reader for a lot less than a dealer would charge.

Once you have diagnostic codes come back here and there are folks who can help you track down the problem.

Ken

 

Which emission specifically was high?
If your ignition is failing that could certainly lead to high hydrocarbon emissions (and a failing cat).

How recent is the ignition?

 

Likely the CAT is has failed...or is not there anymore.....

 

After a bit of research I am going to replace the coils as I don't know when they where changed also it tends to run a bit flat below 3000 rpm hopefully they haven't killed the cat (I did the other day on my cbr 1000 but that's another story)

 

The cat is very easy to check. Pull it and see if the catalyst is clogged or missing. You will definitely want to know about the former, and knowing about the latter doesn't hurt either.

 

I had lack of power under 3000rpm as well, and replacing the coils fixed the problem. I think it was the T2 coil that was starting to fail.

 

Hi all I fitted new coil packs today and it now starts even better than it did before and also the annoying flat spot below 3000 rpm has gone but the emissions are still spectacularly high the lambda sensor is showing below range and even when it goes up into range it is not enough to bring the hydro carbons down anywhere near where they need to be so its off whith the cat next to have a look at that . I think I'm heading in the right direction but if anyone know different please let me know.Rx 8 ownership is a steep learning curve!!!😅

 

You were told what the problem is and what to look for...

You clearly think you know what to do. I don't know why you ask?

What does this even mean?
"the lambda sensor is showing below range and even when it goes up into range it is not enough to bring the hydro carbons down"
You need to provide values. And what are you using to log the data?

The RX8 is a steep learning curve?

 

Thanks for that u clown its people like you that make forums a pain in the butt and for your information I was using the mot test stations gas analyser

 

Team stella... his advice is sound. You haven't actually provided any numeric information for us to give you a hint of what the problem might be.

For example, the lambda sensor just shows air to fuel ratio. You will get "too high emissions" on too lean as well as too rich. But you haven't actually given us numbers for what AFRs you are actually running and when.

If you get an OBD2 adapter, you can plug it in to the OBD2 port, pair it with your smart phone, download an OBD2 app, and then actually read the AFRs that are being commanded, what are being reported, what your MAF values are, what your sensor test results show, what kind of cat temp you are running, if you are getting misfires, etc...

Just giving us vague info isn't letting us help you.

 

Okey dokey point taken but his attitude is still crap ha ha

 

Not everyone gets along with everyone else, and different people have different tolerance levels for what they see as frustrating. Don't let it get to you.

 

ok, I know how MOT testing works

u gotta MAKE SURE your lambda Sensor works (aka O2 Sensor), on MOT test it has to be very close to 1 (0.9-1.1) to be able to pass the test

most likely your Lambda sensor has failed, or close to fail, I just had MOT test (hong kong here) for an rx8 and it passed without a single issue.

 

Pulled the cat off and it's none existent also lambda was 0.4 so I guess that's goosed as well so ordered new stuff I just want the dammed mot so I can go out and play !

 

Well lookit that! whodathunkit!

 

without cat, you will not pass for sure, and ur lambda gonna be wrong (like now)

0.4 lol